3 Nov 2012

31 Oct 2012

1. What causes the occurrence of eclipse of the Moon?
I Light reflection
II Light travels in a straight line
III The position of the Moon between the Sun and the Earth
IV The position of the Moon, the Earth and the Sun in a straight line

A. I and II C. II and IV
B I and III D. III and IV

2. Which of the following is true about the total lunar eclipse?

A. The Earth totally blocks sunlight from reaching the Moon
B. The Earth partially blocks sunlight from reaching the Moon
C. It is dangerous to look at a total lunar eclipse with our naked eyes
D. The Moon totally blocks sunlight from reaching the Earth

3. The phenomenon of eclipse can occur because light
A. travels in a straight line
B. can be absorbed
C. can be reflected
D. can pass through opaque objects

5. During the eclipse of the Moon, its shape changes gradually because
A. the Earth rotates on its axis
B. the Moon rotates on its axis
C. the Earth moves around the Sun
D. the Moon moves around the Earth

6. Which of the following are true about the eclipse of the Sun?

I The Moon is between the Sun and the Earth
II The Moon is not receiving any light from the Sun
III The shadow of the Moon falls on the Earth
IV The Sun and the Earth are in a straight line

A. I and II C. I and IV
B. I and III D. III and IV

7. During the eclipse of the Sun, why does the affected part of the Earth becomes dark?
A. The Sun stops producing light.
B. The sunlight is blocked by the Moon.
C. The Moon reflects sunlight to the outer space.
D. The sunlight is absorbed by a thick cloud.

8. Which of the following is similar between the eclipse of the Sun and the eclipse of the Moon?

A. The Moon, the Earth and the Sun are positioned in a straight line.
B. The Earth is located between the Sun and the Moon.
C. The sunlight is blocked by the Moon from reaching the Earth.
D. The part of the Sun facing the Earth is not producing sunlight for a while.

9. Which of the following phenomena occurs on Earth during the eclipse of the Sun?

I Strong thunderstorm
II Stars can be seen in the sky
III The area concerned becomes dark
IV Animals act aggressively

A. I and II C. I and IV
B. II and III D. III and IV

10. Diagram below shows the eclipse of the Sun.

Among the areas W, X, Y and Z on the Earth, the eclipse of the Sun cannot be seen at area

15 Oct 2012

We know that the Earth revolves round the Sun and the Moon revolves round the Earth. During these revolutions, the Moon may come between the Sun and the Earth along a straight line. When this occurs, the Moon blocks the sunlight from reaching the Earth. This phenomenon is called the eclipse of the Sun.

Phases of eclipse of the Sun
During the eclipse of the Sun, the Moon's has two parts:

The lighter part (also known as penumbra) - where the Moon partly blocks the sunlight.

The dark part (also known as umbra) - where the Moon totally blocks the sunlight.

Partial eclipse of the Sun

A partial eclipse of the Sun happens when only a part of the Sun can be seen. This occurs when only a part of the Sun is blocked by the Moon. We will see less of the Sun when more of it is being 'covered' by the Moon. A partial eclipse of the sun can last from a few minutes to a few hours.

Total eclipse of the Sun

When the Sun is totally 'covered' by the Moon, we call this a total eclipse of the Sun. We only see the Sun as a dark disc surrounded by a bright ring called the corona. A total eclipse of the Sun can last from a few seconds to a few minutes.

Only certain parts of the Earth will experience total eclipse of the Sun while other parts of the Earth will experience a partial eclipse of the Sun.

Additional knowledge

During eclipse of the Sun, darkness suddenly falls during the day. The temperature falls a few degrees centigrade. The whole atmosphere can be very still and eerie. Birds stop singing and butterflies stop fluttering around. Swarm of bees can be seen going back into their hives.